: The unpolarized absorption and circular dichroism spectra of the fundamental vibrational transitions of the chiral molecule, 4-methyl-2-oxetanone, are calculated ab initio. Harmonic force fields are obtained using Density Functional Theory (DFT), MP2, and SCF methodologies and a 5S4P2D/3S2P (TZ2P) basis set. DFT calculations use the Local Spin Density Approximation (LSDA), BLYP, and Becke3LYP (B3LYP) density functionals. Mid-IR spectra predicted using LSDA, BLYP, and B3LYP force fields are of significantly different quality, the B3LYP force field yielding spectra in clearly superior, and overall excellent, agreement with experiment. The MP2 force field yields spectra in slightly worse agreement with experiment than the B3LYP force field. The SCF force field yields spectra in poor agreement with experiment.The basis set dependence of B3LYP force fields is also explored: the 6-31G* and TZ2P basis sets give very similar results while the 3-21G basis set yields spectra in substantially worse agreements with experiment. jg

Ab initio calculation of vibrational absorption and circular dichroism spectra using density functional force fields

Guidelines for the use and interpretation of adsorption isotherm models: A review.

We report an improved synthesis of colloidal gold nanorods (NRs) by using aromatic additives that reduce the concentration of hexadecyltrimethylammonium bromide surfactant to ∼0.05 M as opposed to 0.1 M in well-established protocols. The method optimizes the synthesis for each of the 11 additives studied, allowing a rich array of monodisperse gold NRs with longitudinal surface plasmon resonance tunable from 627 to 1246 nm to be generated. The gold NRs form large-area ordered assemblies upon slow evaporation of NR solution, exhibiting liquid crystalline ordering and several distinct local packing motifs that are dependent upon the NR’s aspect ratio. Tailored synthesis of gold NRs with simultaneous improvements in monodispersity and dimensional tunability through rational introduction of additives will not only help to better understand the mechanism of seed-mediated growth of gold NRs but also advance the research on plasmonic metamaterials incorporating anisotropic metal nanostructures.

Improved Size-Tunable Synthesis of Monodisperse Gold Nanorods through the Use of Aromatic Additives

Spectrometric Identification of Organic Compounds

Studies on surface plasmon resonance and photoluminescence of silver nanoparticles

FTIR and FT-Raman spectrum of 5,6-benzo-2-pyrone were recorded and analyzed. The vibrational wavenumbers were examined theoretically using the Gaussian03 set of quantum chemistry codes. The experimental frequencies are in agreement with the calculated (B3LYP) scaled values. The phenyl and pyrone ring modes are identified and assigned. The predicted infrared intensities and Raman activities are reported.

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Ir, Raman and Dft Calculations of 5,6-Benzo-2-Pyrone

Vibrational spectroscopic and molecular docking study of 4-Methylphenylquinoline-2-carboxylate

A new thermo-optic analysis has been used to detect the photochemical reactions in salbutamol, a drug used as anti asthmatic/bronchodilator. Certain derived optic parameters of pure medicine and that exposed to solar radiations have been determined as a function of temperature. Plots of these parameters versus temperature have been made. The nature of variation and the relative shift in the curves for the exposed samples compared with the unexposed ones have been used to study photochemical reactions. The results have been explained in the light of existing theories and confirmed using UV absorption spectra of the samples.

A Novel Thermo-Optic Analysis to Detect Photochemical Reaction of Salbutamol

Nanoparticles have special physical and chemical properties which are not seen in the bulk material. They are becoming widely used in the various branches of science and technology. Nanoparticles can be prepared from many materials. In this review article, different types of synthesis, characterization and development of new and novel strategies of generation of nanoparticles are discussed.

Hema Tresa Varghese

Papers

Ir, Raman and Dft Calculations of 5,6-Benzo-2-Pyrone

Vibrational spectroscopic and molecular docking study of 4-Methylphenylquinoline-2-carboxylate

A Novel Thermo-Optic Analysis to Detect Photochemical Reaction of Salbutamol

Nanoscience and nanotechnology - A review

Vibrational spectroscopic studies and ab initio calculations of Goniothalamin, a natural product.